Brief Answer:
By eating more of high calorie foods

Detailed Answer:
Hello,

Please let me know your gender, weight and height so that I am better able to help. Please tell in detail about your food habits. Also let me know any medical conditions and medicines that you are taking.

Weight gain can be done by following dietician advice. Dietician will suggest to increase uptake of high calorie foods like milk cream, butter, ghee, cheese, sweets etc.
Also drink cleaner water from RO system. This should help avoid gastrointestinal infections and other infections.
You can raise dietary consult request from your dashboard.
If these measures do not help, then doctor will conduct blood test to find cause of low weight.

Hope this helps. Let me know if I can assist you further.
Dr Vaishalee

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